import java.util.ArrayList;
import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        int[] array = {0, 1, 2, 3};
        System.out.println(Arrays.toString(array));
        String str = "hello";
        System.out.println(str);
    }
    public static void main2(String[] args) {
        Integer a = 100;
        Integer b = 100;
        System.out.println(a == b);//true
        Integer c = 200;
        Integer d = 200;
        System.out.println(c.equals(d));//false
    }
    public static void main1(String[] args) {
        int a = 10;
        Integer b = a;//装箱
        System.out.println(b);
        int c = b;//拆箱
        System.out.println(c);
    }
}